EarleyM.Pipe

Type for "pipes", having multiple writers and readers.

Each element (of type a) written to the pipe is "presented" to each reader (continuation) (of type a -> r).

Elements and readers can be adder in any order. When a new element is added, it is presented to the existing readers. When a new reader is adder, it is presented with the existing elements.

This type is used internally in the implementation of EarleyM, but it may be more widely useful.

Documentation

data Pipe a r

A "pipe" containing elements of type a, and readers of type a -> r.

empty :: Pipe a r

An empty pipe with no elements or readers.

write :: a -> Pipe a r -> (Pipe a r, [r])

Write an element to a pipe, returning the new pipe and presentation results.

read :: (a -> r) -> Pipe a r -> (Pipe a r, [r])

Attach a reader to a pipe, returning the new pipe and presentation results.

firstWrite :: a -> Pipe a r

Create a pipe from a single element.

firstRead :: (a -> r) -> Pipe a r

Create a pipe from a single reader.

elems :: Pipe a r -> [a]

Get the elements of a pipe.

readers :: Pipe a r -> [a -> r]

Get the readers of a pipe.